We studied ion channels, which is exist on the membrane of cochlear hair cells and ganglin cells. These cells play an important role on neurotransmitter mechanism in cochlea. We usued patch-clamp methods. We investigated the effect of ototoxic drugs on mechano-electric transduction channels in chick cochlear hair cells. Cisplatin and Digydrostreptomycin blocked the mechano-electroc trarsduction channel. Two Cisplatin molecules or one dihydrostreptomycin molecule blocked one trarsduction channel. We studied the voltage-dependent ion channels in guinea big outer hair cells. There are two types of potassium channels, one of them is activated even at resting potential. Voltage-dependent calium channel is blocked by aminogycoside antibiotics. This channel was investigated by recording single channel on cell-atlanched mode. We cleared many types of ion channels in cochlear ganglion cells. There are three types of voltage-dependent channels, first the sodium channel, second the calcium channel, and the last the potassium channel. And the chemical receptors, which reponsed by glutamate, was existed on the memnrane of ganglion cells This suggested that the transmitter from the cochlear hair cells to the ganglion cells should be glutamate.